The 14th-seeded Czech pulled a surprise Tuesday with a 7-6 (8-6), 4-6, 6-1 victory over the fourth-seeded Amelie Mauresmo en route to reaching the quarterfinals at Wimbledon.

It was a disappointing result for Mauresmo, the defending champion who never was able to get her game in gear. The Frenchwoman was left frustrated by the 18-year-old Vaidisova, who advanced to the quarterfinals at this grasscourt Grand Slam for the first time in her career.

Mauresmo committed an astounding 37 unforced errors and had 14 double-faults as she was sent packing in a match that was delayed three times by rain.

Vaidisova, who reached the semifinals at the Australian Open and the quarters at the French Open, won despite 31 unforced errors. She had just five double-faults in beating Mauresmo for a third straight time.

A wild backhand from Mauresmo gave Vaidisova a break, allowing her to take a 3-0 lead in the deciding third set. It was the first time more than two games had separated the pair in the match and the gap quickly became insurmountable.

Mauresmo held serve in another closely-contested fourth game with the aid of a 12th ace but she lost it completely in the sixth game, producing two more double faults to taking her total to 14. Mauresmo then produced a poorly executed drop shot on break point and showed her frustration by slamming the ball into the crowd, an act which cost her a code violation.

Mauresmo was quickly put out of her misery, however, with Vaidisova serving out to clinch victory in a match that spanned almost four hours due to the rain. Vaidisova actually won the match in 2 hours, 20 minutes.

In the quarters, Vaidisova will face either sixth-seeded Ana Ivanovic or number 11 Nadia Petrova.

Fifth-seeded Russian Svetlana Kuznetsova coasted into the quarterfinals with a 6-3, 6-2 victory over Tamira Paszek. It marks the third time that Kuznetsova has reached the round of eight at Wimbledon.

Kuznetsova did have her match against her 16-year-old Austrian opponent halted by rain after the first set. However, it hardly slowed her down as she needed a mere 54 minutes to advance.

"It was pretty comfortable. She started very well, but I felt like during the match like I put in more and more pressure on her," Kuznetsova said. "She was playing worse, worse, worse.

So for me it was better. I was getting more confidence. I was trying to play better. She went a little bit low. Yeah, I expected a very tough match, but I'm happy. Every round my performance grows, so I'm happy about it."

Using some powerful groundstrokes and just looking confident in her overall game, Kuznetsova fired 22 winners, compared to just six for Paszek, who was overmatched from the outset.

Kuznetsova next will face either second-seeded countrywoman Maria Sharapova or American Venus Williams. "I'm happy with my performance, because I start playing not so good my first match and now I'm playing better than ever I played in this tournament," Kuznetsova said. "Really enjoy the game on grass. Now I start loving it, so it's good."

Play was twice delayed early in the match, each time for about 20 minutes. The third delay came when Mauresmo was about to serve for the second set, and lasted nearly an hour.

This year's tournament has been hampered by rain in seven of its first eight days.

Matches on Centre Court and Court number one started at 11 a.m. Tuesday -- two hours earlier than usual -- because of the backlog of matches.

On the men's side, 2003 French Open champion Juan Carlos Ferrero reached the Wimbledon quarterfinals for the first time by beating Janko Tipsarevic in straight sets.